In the French Pat. No. 76 35439 published under No. 2370874 filed Nov. 16th, 1976 by the applicant, there is described a turbine rotating at speeds of the order of 3000 rotations per minute for example and adapted to drive tools such as brushes or the like, intended especially for underwater operations.
This turbine can be driven by a motor pump providing water under a pressure or several bars with an output of the order of one to several tens of cubic meters per hour, and permits the construction of portable apparatuses.
According to the said patent, the turbine comprises a distributor presented in the form of a passage without blades which communicates, with the blades of a rotor with four blades, by means of injectors constituted by openings formed between portions of a circular stator ring, in number double that of the blades, the water escaping axially to the centre of the rotor chamber.
Subsequent work of the applicant has permitted him to discover that such a turbine only functions correctly and with a satisfactory output if a certain number of conditions of shape and of dimensions are respected.
Consequently, the turbine according to the invention is principally characterised in that the blades have a profile of an arc of a circle, that the portions of the stator ring which define the injectors each have a plane terminal face inclined at substantially 45.degree. to the corresponding radius of the respective portion of ring and, for a first injector, forming an angle substantially equal to 135.degree. with the plane tangential to the external surface of the corresponding blade, when this latter occupies a position in which an adjacent blade is on the point of commencing to cooperate with the respective injector.
According to another feature of the invention, in the said position of a blade, it cooperates with a second injector the plane terminal face of which forms an angle substantially equal to 120.degree. with the plane tangential to the external surface of the said blade and the difference of inclination of the two consecutive jets acting on the same blade is always substantially equal to 15.degree..
Another feature of the invention is that the ratio between the external radius of the said arcs of a circle and the internal radius of the said stator ring is substantially equal to 3/4.